a)
[tex] \frac{200}{1} \times \frac{40}{100} = \frac{2}{1} \times \frac{40}{1} = \frac{80}{1} [/tex]
200 - 80 = 120
80 chłopców 120 dziewczynek
b)
[tex] \frac{200}{1} \times \frac{40}{100} = \frac{2}{1} \times \frac{40}{1} = \frac{80}{1} [/tex]
200 - 80 = 120
120 g wody i 80 g soli